Im rebuilding my 96 fj80 ,locked(totaled by ins, co.) among the damaged is the front housing (bent on the R side) Ill be switching the third member to another housing , Im thinking about a gear change does anyone know what the RPM difference would be of hand (4.10 to 4.88) Im running 285/75/R16s now rpm est @ 70mph? THANKS. TC
410s to 488s
- Thread starter Tango Charlie
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That's a very simple calculation. It would be 488/411 which equals 1.187. Therefore, your rpm would be 18.7% higher. For example, if you normally ran 2000 rpm at a certain mph, you would now be running 2375 rpm (2000 x 1.187) to obtain the same speed (assuming the transmission was in same gear).
Of course this example assumes that you aren't changing tire sizes as well. If so you would have to then ratio the rpm back down (or up for smaller tires) based on the tire diameters.
There are lots of gear ratio "calculators" on the internet if you just google ring and pinion ratio calculator.
Of course this example assumes that you aren't changing tire sizes as well. If so you would have to then ratio the rpm back down (or up for smaller tires) based on the tire diameters.
There are lots of gear ratio "calculators" on the internet if you just google ring and pinion ratio calculator.
4.88 is a great gear ratio for general use and also for most diesel conversions. 5.29 is recommended for serious off-road application. What are you going to be using it for?
Here is a good site for the ratio calculations http://www.csgnetwork.com/rnggrpinioncalc.html
Hope this helps:
https://forum.ih8mud.com/80-series-tech/124774-4-56-vs-4-88-been-there-done.html
Might wanta search: select 80's section (use key words like 4:88)
Hope this helps.
https://forum.ih8mud.com/80-series-tech/124774-4-56-vs-4-88-been-there-done.html
Might wanta search: select 80's section (use key words like 4:88)
Hope this helps.
I have 4.88s and am running 33s for the winter. You definitely lose top speed with this combo, as you need to wind the piss out of the motor to get to 70. But it's impressive at lower speeds.
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Questions answered
Thanks for the Info everyone I'm guessing that Im running around a tire size of 33's now so the 4.88s might have to wait for the second round of modifications when she is'nt used so much for long distance commuting or I go to bigger tires Later TC
Thanks for the Info everyone I'm guessing that Im running around a tire size of 33's now so the 4.88s might have to wait for the second round of modifications when she is'nt used so much for long distance commuting or I go to bigger tires Later TC
I run 4:88's with 33's that measure a hair over 32"es tall. At 70 I'm running about 2700 RPMs. BUT, I have the 3FE, and older tranny. I can run 100 MPH with little effort in the flats, and at about 4000 rpm. Yea I know, not the smartest thing to do, but my point is the engine isn't wound out at all with the 3FE. Can't imagine it would be that much different for the 1FZE.